On Guard

When you take time to smell the flowers, or rather peer at the onions, you find some pretty cool stuff. This week, Simon shared with me another little gem of nature: parasitized natural enemies. Just a reminder, parasitoids develop internally on their host, usually killing it. This particular case of parasitism, however, is atypical in that the host does not die

Image courtesy of Maure et al. 2011

The victim of the story is the common Pink Lady Beetle, Coleomegilla maculata, affectionately called C-mac in some circles. C. maculata is a generalist predator, feeding on aphid species and other small soft bodied insects. I’m not surprised to see many of them in the onion fields. In this case, a parasitic wasp, Dinocampus coccinellae, lays a single egg inside its beetle host. Rather than killing the host, the wasp larva emerges and spins its pupal casing around the legs of the ladybug, keeping it in place. Thereby, providing its own bodyguard to protect it from predation and hyperparasitism (parasitoids that parasitize other parasitoids…that’s a lot of parasitism). This article was just published online about the system. Pretty cool!